Osteonecrosis of the Jaw
Also written as: ONJ — Osteonecrosis of the Jaw
A condition characterised by exposed, necrotic bone in the jaw persisting for more than eight weeks in the absence of prior radiation therapy.
Full Definition
Osteonecrosis of the jaw (ONJ) is a severe oral complication defined by exposed bone in the maxillofacial region that fails to heal over eight weeks in a patient who has not received radiotherapy to the jaws. It is most frequently associated with antiresorptive or antiangiogenic drug therapies and is then specifically termed MRONJ (medication-related osteonecrosis of the jaw). Editors should note that ONJ is the broader, inclusive term, while MRONJ and osteoradionecrosis (ORN) are aetiologically distinct subtypes. The abbreviation ONJ should be expanded on first use in all document types. Staging systems (AAOMS 2014) are commonly referenced in clinical manuscripts.
Usage
Usage note: ONJ is the umbrella term; do not use it interchangeably with MRONJ or osteoradionecrosis, which are aetiologically specific subtypes.
In Context
- "The guidelines distinguish osteonecrosis of the jaw from osteoradionecrosis by the absence of any prior radiotherapy to the head and neck region." — Clinical guideline document
- "Ensure 'osteonecrosis of the jaw' is abbreviated as ONJ after first use, not confused with ORN throughout the manuscript." — Copy-editing instruction